Diallyl disulfide induces apoptosis in human leukemia K562 cells through activation of NADPH oxidase / 中国药理学通报

ABSTRACT

Aim Toresearchthemolecularmecha-nisms of DADS-induced apoptosis in human leukemia K562cells.Methods Cellviabilitywasmeasuredby MTT. Levels of DADS-induced ROS were measured by 2ˊ, 7ˊ-dichlorofluorescein diacetate ( DCFH-DA) fluo-rescence. DADS-induced mRNA levels of components of the NADPH oxidase were detected by Real-time PCR. The combination of protein Rac2 and p67phox was measured by immunoprecipitation assays. Flow cy-tometry methods were used to determine the percentage of apoptosis cells. DADS-induced Rac2 levels were measuredbyWesternblot.Results TheDADS-trea-ted K562 cells showed a dose-and time-dependent de-crease in cell viability and proliferation. There was sig-nificant up-regulation of the mRNA level of components of the NADPH oxidase complex in K562 cells after treatment with 6 mg·L-1 DADS for 6 h. Western blot results revealed that, compared with the control group, there was a significant up-regulation of Rac2 protein in K562 cells treated with 5. 0 and 10. 0 mg·L-1 DADS for 24h. And Rac2 combined with p67phox in DADS-induced apoptosis in K562 cells. PMA markedly in-creased the percentage of apoptotic cells, and DPI re-duced the percentage of apoptotic cells in DADS-in-duced K562 cells. Levels of DADS-induced ROS, also showed enhancement when exposed in PMA, but there was no DADS-induced ROS production evident when exposed in DPI in DADS induced K562 cells. Conclu-sions TheseresultsindicatethatNADPHoxidaseis the main source of DADS-induced ROS production. Diallyl disulfide induces apoptosis in human leukemia K562 cells through activation of NADPH oxidase.